Unable to purchase character boost

Good day,

So it turns out that regardless of being able to link a US WoW Shadowlands to an EU battle.net account, you can still not make a purchase like character boost.
The character boost is only available via in game yet in game wants to link you back to the store page where the button is greyed out.

You get an in game error relating to your region “We see that you are trying to buy Shadowlands-Level Character Boost in a different region than your Blizzard account region. To complete your purchase, visit the Blizzard web Shop (US).”
The shop then shows “Available for in-game purchase” so this is a clear indication that I cannot purchase the character boost through either of your “available” services.

After submitting a support ticket telling Blizzard that I want to spend money on this, I was advised that this is out of the hands of support and all changes are done by the devs.

I was advised I need to update my account region to US to complete the purchase but cannot complete this as I do not reside in the US and can therefore not provide proof of US residency.

Has anyone been able to get assistance regarding the above explained scenario from a support GM or have a work around for how to go about purchasing character boost?
I am essentially locked out of all character services.

Hope anyone has some work around for this.

Thanks in advance.